You can sign up for a free account to track your videos and create a favorites list, or you can just view videos. The videos are great quality and explain the topics well. There are also suggested videos that are more basic than the one you are watching (going back) or more advanced (going forward). They also have bundles, which are collections of videos that are grouped together by topic.
This is a great resource for students and educators for their own use, as well as to provide free tech training for them in school.
Related:
How to Support others with Tech Help